[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
Re: On the subject of "arbitrary" paleontology
In a message dated 5/28/99 3:05:47 AM Eastern Daylight Time,
Z966341@wpo.cso.niu.edu writes:
<< In experimental sciences,
chemical assays are run or protons are smashed together again and
again, the data compiled and analyzed and compared. In historical
sciences, scientists look at the same defined characters as the
original researcher (usually hoping to falsify the hypothesis). >>
These are two different procedures, one data gathering, the other reviewing a
hypothesis. Also, don't different scientists look at different characters,
searching for monophyly?
<<As frustrating as it may be, we cannot re-run evolution again and
again -- but this does not make paleontology any less scientific than
physics or chemistry. We are under a different set of constraints and
problems.>>
Yes.
On repeatability, though, when 'cold fusion' was discovered or the sheep was
cloned other scientists did not ask for the lab notes or even the sheep.
They asked for the recipe which would allow them to do the same thing in
their labs. The concern is repeatability of the process of making something.
As you say, we cannot 're-run evolution again and again'. One of the
'constraints and problems' is the absence of this kind of repeatability.
(By the way, I just read that Dolly the cloned sheep's telomeres caps on her
chromosomes--they prevent the genetic material from fraying--have been
wearing down unusually quickly. This may or may not be because she was
cloned from a 6 year old sheep.)
<<Predicting relationships of animals and relativity theory are in the same
boat. Both can be falsified. The prediction of relationships is the risky
part! All it takes is one fossil, a new date, a re-examination of already
collected material, and your hypothesis is destroyed, not extended.>>
Assuming that the original interpretation was logical and included all of the
available data, 'a re-examination of already collected material' is not as
significant a danger as changes in the data itself. The existence of a
logical, inclusive alternate interpretation does not automatically invalidate
another interpretation, though it does hint at insufficient data.
Leaving aside how vulnerable cladistic interpretations are to questions about
time, as implied by 'a new date', the connection being stated involves known
animals. As I understand prediction, this has to involve things that have
not occurred or at least been studied yet.
The closest thing to a prediction I can think of is a statement like, 'If
these two animals are related as I say, then a fossil will be found in this
place dating from this time with these characters.' A hypothesis could wait
a long time to be supported/refuted in this way. There are theories in
physics with the same problem, I understand.
<<What's wrong with parsimony? What's your solution or how would you address
this?>>
I don't have the knowledge or experience of the people who decided to use
parsimony as a way to evaluate theories. However, the need for something
like parsimony in forming judgements does show that the data itself is
insufficient to support/refute theories.
<< Plate tectonics was not accepted as scientific theory not because it
didn't agree with the particular paradigm or reigning world view of the
scientific elite. It was not accepted because its original proposers had no
mechanism for how it worked. Wegner had a great idea, but great ideas in
science need mechanisms and testability.>>
Hmmm. Evolutionary biology hasn't completely sorted out the
mechanism-related issues of mutation, selection, etc., has it? Sometimes
evidence of an effect can be sufficient. My point, though, was that people
do tend to get 'invested' in an idea they have held for years and become less
than eager to change their minds. I think you can agree with that?
<<Reasonable argument usually ends when most scientists are satisfied with
how the hypothesis fits the available evidence. It will never be completely
objective, and you will never have complete agreement.
Sorry, that is very frustrating! =)>>
Here we have reached agreement! (Notice how your second sentence modifies
the first.) Just add your point that paleontology inevitably has 'a
different set of constraints and problems' from other sciences (I'd add:
which limit its application of the scientific method), and the Socratic
method has worked again!
As you say, this is fun.